Justplain
4th April 2017, 21:08
I saw this article on google news, a technological enhancement that has far reaching implications, such as providing drinkable water for millions and allowing irrigation for vast tracks of desert land.
(CNN) Researchers in the United Kingdom have developed a graphene-based sieve that can filter salt out of seawater, a development that could provide drinking water to millions of people around the globe.
The applications could be a game-changer in countries where access to safe, clean, drinkable water is severely limited.
Graphene -- an ultra-thin sheet of carbon atoms organized in a hexagonal lattice -- was first identified at the University of Manchester in 2002 and has since been hailed as a "wonder material," with scientists racing to develop inexpensive graphene-based barriers for desalination on an industrial scale.
Now, the team at Manchester has used a compound of graphene, known as graphene oxide, to create a rigid sieve that could filter out salt using less energy.
Overcoming hurdles:
In recent years, there had been some success in water filtration using graphene oxide to sift out other smaller nanoparticles and organic molecules.
But researchers had struggled to move forward after finding that the membrane's pores would swell up when immersed in water, allowing particles to continue to pass through.
Rahul Nair's team at Manchester now claims it has discovered how to control of the expansion and size of the pores.
Writing Monday in the Nature Nanotechnology journal, the team revealed it was able to restrict pore-swelling by coating the material with epoxy resin composite that prevented the sieve from expanding. This means common salt crystals could continue to be filtered out, while leaving behind uncontaminated, clean, drinking water.
The discovery is "a significant step forward and will open new possibilities for improving the efficiency of desalination technology," Nair said in a statement from the university.
"This is the first clear-cut experiment in this regime. We also demonstrate that there are realistic possibilities to scale up the described approach and mass produce graphene-based membranes with required sieve sizes," he added.
Global implications:
Boosting global access to water is critical. By 2025, 14% of the global population will suffer from water scarcity, the United Nations predicts. In addition, climate change is expected to wreak havoc on urban water supplies, with decreased rainfall and rising temperatures expected to fuel demand.
http://www.cnn.com/2017/04/04/health/graphene-sieve-drinkable-seawater/
(CNN) Researchers in the United Kingdom have developed a graphene-based sieve that can filter salt out of seawater, a development that could provide drinking water to millions of people around the globe.
The applications could be a game-changer in countries where access to safe, clean, drinkable water is severely limited.
Graphene -- an ultra-thin sheet of carbon atoms organized in a hexagonal lattice -- was first identified at the University of Manchester in 2002 and has since been hailed as a "wonder material," with scientists racing to develop inexpensive graphene-based barriers for desalination on an industrial scale.
Now, the team at Manchester has used a compound of graphene, known as graphene oxide, to create a rigid sieve that could filter out salt using less energy.
Overcoming hurdles:
In recent years, there had been some success in water filtration using graphene oxide to sift out other smaller nanoparticles and organic molecules.
But researchers had struggled to move forward after finding that the membrane's pores would swell up when immersed in water, allowing particles to continue to pass through.
Rahul Nair's team at Manchester now claims it has discovered how to control of the expansion and size of the pores.
Writing Monday in the Nature Nanotechnology journal, the team revealed it was able to restrict pore-swelling by coating the material with epoxy resin composite that prevented the sieve from expanding. This means common salt crystals could continue to be filtered out, while leaving behind uncontaminated, clean, drinking water.
The discovery is "a significant step forward and will open new possibilities for improving the efficiency of desalination technology," Nair said in a statement from the university.
"This is the first clear-cut experiment in this regime. We also demonstrate that there are realistic possibilities to scale up the described approach and mass produce graphene-based membranes with required sieve sizes," he added.
Global implications:
Boosting global access to water is critical. By 2025, 14% of the global population will suffer from water scarcity, the United Nations predicts. In addition, climate change is expected to wreak havoc on urban water supplies, with decreased rainfall and rising temperatures expected to fuel demand.
http://www.cnn.com/2017/04/04/health/graphene-sieve-drinkable-seawater/